Yamaha Electone EL-87 Owner's Manual page 93

EDIT Page
At the left side of the display is the Algorithm used for this
voice. An algorithm is a kind of "map" that shows how the
sound components of the voice are related to each other.
Each voice has five separate sound components and they
are called "Operators."
3
Begin changing the sound by turning off all Operators, except
Operator 1.
To turn off each Operator:
1. First, use the pair of Data Control buttons just below the
algorithm display (below the box 1; the second from the left) to
select an Operator.
The currently selected Operator number is surrounded by the
"Brackets".
Pressing the [Å¢] button move the "Brackets" counter clockwise,
and pressing the [ŧ] button move the "Brackets" clockwise.
Move the "Brackets" to the Operator 2.
2. Then press one of the far left pair of Data Control buttons to
turn the selected Operator off.
3. Repeat the above process for all of the Operators except Operator 1.
As you turn off each Operator, play the voice and listen to how
the sound changes.
When you turn off the AWM Operator, no sound will be
produced.
N O T E :
The currently selected Operator name is
shown in the dark bar in the middle of the
display.
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